The objectives of the project are: To study the biochemical events related to growth and regression of experimental hormonally dependent mammary carcinomas which mimic human cancers. To investigate the mechanisms of microsomal G6PD activity disappearance in DBcAMP induced regressing tumors which will elucidate the role of the cyclic AMP system in tumor regression. Also, to study the correlation between tumor regression induced by hormonal deprivation with that induced by DBcAMP treatment.